Cockpit Wings??

[Astro]

Hi All, would anyone like to comment, on whether or not I should include cockpit wings on my car? Photos to follow. First photo is cockpit without extensions.
I am rebuilding an FJ1600 for hillclimb and sprint use and I have moulded some pieces which would surround the cockpit to limit the migration of airflow from the top of the sidepods into the cockpit. My theory is that the airflow would form a vortex trailing off to the rear. My question is should I bother with these pieces? I've researched to try to find some example of a similar device but there does not seem to be any evidence of such an item that I have found.
Any comments welcome.
Astro.

[Purple Frog]

I would think making a proper safe seat would be more important than the small aero improvement you are seeking.

That green seat would be a real back breaker in a bad shunt.

Just saying...

[S Lathrop]

My experience has been that the airflow over the cockpit opening comes straight up the front of the cowl. On one of my cars (my design), a FSV, that flow was so strong that I could not hold my head up against the air flow. For that car, my fix was a horizontal plate around the front of the cockpit opening, much like what you are doing around the sides. Interestingly this same plate worked really well in the rain. I used that cowl shape on many cars after that.

I would put my effort into having a good flow of air out of the back of the cockpit. Ideally the rear of the cockpit should be a couple inches lower than the front. I use 2 inch difference on my cars. I use the head surround to smooth the airflow around the driver's head and out of the cockpit.

The cockpit opening rules used internationally dictate a minimum height of the fire wall and this makes it tough to get the flow out of the cockpit optimized.

[MotorCade]

I'd imagine those winglets would be really easy to break off on ingress/egress.

[Rick Kirchner]

Wow - an Apexer in Lismore. My daughter did a semester at Southern Cross a few years back.

[R. Pare]

Take a close look at the head surrounds used on F1, F3, Indy, etc., cars to see what wind tunnel data has produced - they are not only a safety item, but help smooth the airlow over the dirvers shoulders and on to the engine cover.

And yes, get rid of the plastic seat and make a proper bead seat, or at least a foam seat.

[dogrings]

Hi As chief of tech at VARA in Calif. That seat would definitely not be allowed as it is. Fill the volume behind seat to firewall with expandable foam is better but a real seat with beads fitted to you and the area in front of the firewall much safer. I have been doing this stuff for 60 years and seen too many terrible back injuries.
Wayne Mitchell --dogrings.com

[Astro]

Thanks Guys for your comments, It looks like I will making a new seat for my car. A couple of questions if I may whilst I have your attention. Should I make an aluminium shell which would house the beads, and be bolted to the frame? I want to be able to remove the seat. I could then insert foam between the seat shell and the firewall. What type of foam would be suitable between the seat and firewall?
Hi Rick Kirchner, yes even in small country towns like Lismore we love our motorsport. Being so far removed from the motorsport mainstream, we just have to try harder, I think.

Astro.

[S Lathrop]

Thanks Guys for your comments, It looks like I will making a new seat for my car. A couple of questions if I may whilst I have your attention. Should I make an aluminium shell which would house the beads, and be bolted to the frame? I want to be able to remove the seat. I could then insert foam between the seat shell and the firewall. What type of foam would be suitable between the seat and firewall?
Hi Rick Kirchner, yes even in small country towns like Lismore we love our motorsport. Being so far removed from the motorsport mainstream, we just have to try harder, I think.

Astro.

You can have a simple sheet metal cover over the components that will be behind the seat.

Get a couple large trash can liners, %% gallon types. Next get some 2 part foam, 3 pound density. I refrigerate the foam so it expands slower. Double the bag and place them where the seat goes. Mix the foam in small quantities, one quart or less at a time. pour the first batch of foam into the seat and jump in the car. work the foam around as it expands. Add foam until you have a full seat.

You will probably make a couple seats until you get the process down. Once you have something that you are satisfied with, you can go get a proper seat kit and make the final product. Or just use the seat you make with the foam. You can finish the seat with duct tape instead of the plastic bags you foamed it in.

[Revs2-12k]

Astro,

G-Day.......Back on topic.

We spent a bit of time on this during the 2 hours of wind tunnel testing at the A2 Wind Tunnel in Mooresville, NC with the designer of my Stohr F1000 - Wayne Felch. The video's taken were very helpful, especially when we analysed the still shots. See below.

https://www.youtube.com/watch?v=9sd91yXelTM

Couple of notables and the changes we made.
The small hole in the Stohr nose is effective.
Windscreen (made from a Bell Helmet shield) dramatically reduced helmet buffeting.
Changed to Aero mirrors.
Added the Dangerous Cargo DRD to the GoPro

[Daryl DeArman]

I love the "think" reminder. I had one that said "Patience" for a couple of seasons.

[B Farnham]

Astro,

G-Day.......Back on topic.

We spent a bit of time on this during the 2 hours of wind tunnel testing at the A2 Wind Tunnel in Mooresville, NC with the designer of my Stohr F1000 - Wayne Felch. The video's taken were very helpful, especially when we analysed the still shots. See below.

https://www.youtube.com/watch?v=9sd91yXelTM

Couple of notables and the changes we made.
The small hole in the Stohr nose is effective.
Windscreen (made from a Bell Helmet shield) dramatically reduced helmet buffeting.
Changed to Aero mirrors.
Added the Dangerous Cargo DRD to the GoPro

Very interesting stuff, where does the air that enters the nose exit? Is it underneath the nose?

[Marty Nygard]

Since the F1000 rules say:
"There shall be no forward facing gaps or openings in the bodywork with the exception of those necessary for engine cooling, engine air inlet, shock, or brake cooling."
I question the legality of the nose opening.
M

[Revs2-12k]

BFarnham, to answer your question, it cools the front shocks first.

[Hardingfv32]

Exactly what is wrong with the green seat?

How are backs (not necks) typically broken in accidents? What exactly happens to the back to cause injury?

Brian

[Steve Demeter]

Many major sanctioning bodies require a minimum thickness of foam (bead seat stuff) under the drivers butt and back.

The green seat is apparently rigid and will transmit any impact to the river's body no matter what the direction.

The foam attenuates the impact by crushing like a helmet liner.

Nothing wrong with the green seat except that there are a whole lot of better alternatives that do not cost much.

The foam under the driver's butt is to help in the event of a hard landing which could cause a compression fracture of the back / spine.

[a. pettipas]

I love the "think" reminder. I had one that said "Patience" for a couple of seasons.

I find it concerning that anyone getting in a race car needs a reminder to think.

Exactly what is wrong with the green seat?


How are backs (not necks) typically broken in accidents? What exactly happens to the back to cause injury?

Brian

Is this a real question? That's a go-kart seat.

[R. Pare]

Exactly what is wrong with the green seat?

How are backs (not necks) typically broken in accidents? What exactly happens to the back to cause injury?

Brian

Plastic seats, when not properly supported on their backside, can easily break in half in a rearward crash, in turn breaking the drivers back. If you ever meet him, ask Craig Taylor why he is now a half-inch shorter than he was before his crash 20 years ago.

[DaveW]

Not to joke about breaking one's back, but all us old guys are at least 1/2" shorter than we were 20 years ago...

[cjsmith]

Astro,
I agree with everyone point on the seat being more important and also doesn’t look like it would hold you in place or be comfortable at speed. Back to your original question about the wing lets or a version of a dive plate along the edge of the drivers compartment. Looking at the design of your body work just behind the shocks, I would expect you would still have laminar flow along the vertical portion of the body work but as get near the upper edge I would expect you will have flow separation or turbulent flow due to the design of the lips and edges of the body work as you get closer to the top of the driver compartment opening. Hence having disturbed air going over the lip you are proposing. I would expect this would negate any down force you may be trying to create. I’m not all that familiar with what speeds you can get up to on a hill climb would think you would get more benefit from adding a rear under tray and lifting it up at the back end, (within the rules) would provide better negative lift without the drag penalty. Not sure if you are going to be taking your engine air inlet from the raised section between the roll bar or not. If you are, hope the opening will be above your helmet or you will not be building much static pressure in the plenum.

Chris

[OneWayOut]

Added the Dangerous Cargo DRD to the GoPro

Neat. I have been thinking about making one of those for myself.

Can you buy those somewhere? I don't see a price on their website.